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140 Cards in this Set

  • Front
  • Back
Chap 2
Describe the three layers of meninges:

The meninges are composed of three connective tissue membranes that surround the spinal cord and brain.

1. pia mater: delicate, highly vascular layer. It closely covers the surface of brain and spinal cord.
2. arachnoid: delicate, nonvascular. Between pia and dura.
3. Dura mater: outer layer, very dense.
Chap 2
What are the three meningial spaces?
1. subarachnoid space: between pia and arachnoid. Contains the CSF. Ends at second sacral level.

2. Subdural space: in the crainium it is crossed by bridging veins (not significant in spine)

3. Epidural space: cranial epidural space contains meningeal arteries and veins; spinal epidural space contains fatty areolar tissue, lymphatics, and venous plexuses.
Chap 2

Where is local anesthetic injected to produce a paraverterbral "saddle" nerve block?
Spinal epidural space
Chap 2

What is a meningioma?
FA p.362/HY p.21

Meningioma: second most common primary brain tumor. It is benign, well-circumscribed, and slow growing.
More common in women
90% are supratentorial
Found in convexities of hemispheres and parasagittal region
Arises from arachnoid cells external to brain

Spindle cells concentrically arranged in a whorled pattern: psammoma bodies (laminated calcifications)
Chap 2

What is a subdural hematoma?
FA p.362/HY p.21

Subdural hematoma: is caused by laceration of the superior cerebral (bridging) veins.
Venous bleeding (less pressure) with delayed onset of symptoms.
Seen in elderly individuals, alcoholics, blunt trauma, shaken baby
Predisposing factors: brain atrophy, shaking, whiplash.
Chap 2

What is a epidural hematoma?
FA p.362/HY p.21

Epidural hematoma: laceration of middle meningeal artery, often secondary to fracture of temporal bone.
Lucid interval (see color image 44)
CT shows "biconvex disk" not crossing suture lines.
Chap 2

Describe cytomegalovirus induced encephalitis:
RR p.578

Most common viral CNS infection in AIDS
Most common congential infection in kids
Primary intranuclear basophilic inclusions
Periventricular calcifications in newborns.
Chap 2

What body fluid is best used to diagnose congenital cytomegalovirus?
RR p.578

Chap 2

Describe rabies virus encephalitis?
RR p.578

Rabies: most often transmitted by skunk
Virus ascends peripheral nerve
Neurons contain intracytoplasmic Negri bodies
CNS excitability stage followed by flaccid paralysis.
Chap 2

What is Creutzfeldt-Jakob disease? VIP!
RR p.579

Unconventionally slow virus encephalitis due to prions (proteinaceous material devoid of RNA or DNA)
Transmitted through corneal transplantation or contact with brain tissue, or ingestion of meat infected with bovine spongiform encephalopathy
Brain has "bubble and holes" spongiform change in cerebral cortex.
Death usually occurs within 1 year.
Chap 2

What is the most common cause of neonatal meningitis?
RR p.579

Group B streptococcus, Strep Agalactiae
Gram positive coccus
Spreads from a focus of infection in maternal vagina
Chap 2

What is the second most common cause of neonatal meningitis?
RR p.579

E. Coli:
gram (-) rod
Chap 2

What is the most common cause of meningitis in those between 1 mth and 18 yrs?
RR p.579

Neisseria Meningitidis
Chap 2

Why shouldn't pregnant women eat soft cheeses?
RR p.579

Soft cheese has listeria monocytogenes which is the third leading cause of neonatal meningitis
Chap 2

Describe Listeria monocytogenes, an organism that can induce neonatal meningitis:
Listeria is a gram positive rod with tumbling motility (like trichomonas)
Chap 2

What is the most common cause of meningitis in someone > 18 yo? Describe organism?
RR p.579

Strept pneumoniae
Gram + diplococcus
Chap 2:

Goljan Q: 50yo main with meningitis most likely has:
a. gram + coccus
b. gram - rod
c. gram + rod
d. gram + diplococci
D: Strept pneumoniae is a gram + diplococci

gram + coccus: group B strept agalactiae
gram - rod: e. coli
gram + rod: listeria
Chap 2

CSF findings in bacterial meningitis? (3)
Bacterial meningitis
1. many PMM leukocytes
2. decreaed glucose
3. increased protein
Chap 2

CSF findings in viral meningitis? (3)
Viral meningitis
1. many lymphocytes
2. normal glucose
3. increaed protein
Chap 2

What is the choriod plexus?
Choroid plexus is a specialized structure that projects into the ventricles.
It is made of blood vessels from the pia mater that are covered in ependymal cells that secrete CSF.
Chap 2

What forms the blood-CSF barrier?
Tight junctions of the choroid plexus cells form the blood-CSF barrier.
Chap 2

How do the two lateral ventricles communicate?
Through the third ventricle via the foramina of Monro
Chap 2

How does the third ventricle communicate with the fourth?
Via the cerebral aqueduct
Chap 2

How does the fourth ventricle communicate with the subarachnoid space?
Via two foramen called lateral foramina of Luschka
One medial foramen of Magendie
Chap 2

What is noncommunicating hydrocephalus?
Hydocephalus caused by an obstruction within the ventricles - most commonly: congenital aqueductal stenosis)
Chap 2

What is communicating hydrocephalus?
Hydroceph caused by blockage within the subarachnoid space (commonly caused by pus adhesions after meningitis)
Chap 2

What is normal-pressure hydrocephalus?
Hydroceph in adults caused when CSF is not absorbed by the arachnoid villi.

Clinical features: wacky, wobbly, wet (dementia from dilated ventricles, ataxic gait, urinary incontinence)
Chap 2

Hydrocephalus ex vacuo?
A loss of cells in the caudate nucleus

Most common cause in Huntington's disease.
Chap 2

Three main functions of the CSF?
1. protects against injury
2. transports hormones
3. removes metabolic waste products
Chap 2

RBC's in CSF =
Subarachnoid hemorrhage
Chap 2

What is an uncal herniation?
FA p.367/HY p.25

When the uncus, the medial temporal lobe, herniates through the tentorial incisure.
Chap 2

What are the clinical signs assocated with uncal herniation? (4)
FA p.367

Uncal herniation:
1. ipsilateral dilated pupil/ptosis: stretching of CN III

2. contralateral homonymous hemianopia: compression of ipsilateral posterior cerebral artery

3. ipsilateral paresis: compression of contralateral crus cerebri (Kernohan's notch)

4. duret hemorrhages - paramedian artery rupture: caudal displacement of brain stem.
Chap 2

Herniation figure:
1. anterior cerebral artery
2. subfalcial herniation
3. shifting of ventricles
4. posterior cerebral a
5. uncal herniation
6. Kernohan's notch, with damaged corticospinal and corticobulbar fibers
7. tentorium cerebelli
8. pyramidal cells that give rise to the corticospinal tract
9. tonsillar herniation with damage to medullary centers.

HY p.25
Chap 2

Herniation syndromes (FA p.367)
Herniation syndromes

1. Cingulate herniation: can compress anterior a
2. Downward transtentorial (central) herniation: coma and death result
3. Uncal: coma and death
4. Cerebellar tonsillar: herniation into foramen magnum
Chap 3

What does the anterior spinal artery supply?
Anterior spinal artery:
1. anterior 2/3 of spinal cord
2. medulla's pyramid
3. medial lemniscus (also of medulla)
4. root fibers of CN 12
Chap 3

What artery branches off the ophthalmic artery to feed the retina? What runs with the opthalmic artery?
Opthalmic artery enters the orbit with the optic nerve (CN II). The central artery of the retina is a branch of the ophthalmic artery and occlusion of either causes blindness.
Chap 3

What does the anterior cerebral artery supply?
FA p.347

Anterior cerebral a: supplies medial surface of the brain - the area of the brain that controls the leg-foot area of motor and sensory cortices.
Chap 3

What does the middle cerebral artery supply?
FA p.347

MCA: lateral aspect of brain, trunk-arm-face area of motor and sensory cortices
as well as Broca's and Wernicke's speech area
and frontal eye field
Chap 3

What does the anterior communicating artery do?
FA p.347

The ACA is the most common cite of circle of willis aneurysm;
lesions here can cause visual field defects.
Chap 3

Posterior communicating artery?
FA p.347

PCA: other common aneurysm location, causes CN III palsy.
Chap 3

Lateral striate
FA p.347

Lateral striate: branches of middle cerebral artery
"arteries of stroke"
supply the internal capsule, caudate nucleus, putamen, and globus pallidus
Chap 3

In general, a stroke of the anterior circle causes what?
Anterior circle:
1. general sensory and motor dysfunction
2. aphasia
Chap 3

In general, a stroke of the posterior circle causes what?
Posterior circle, FA p.347
1. cranial nerve deficits (vertigo, visual deficits)
2. coma
3. cerebellar deficits (ataxia)
Chap 3

What runs in the cavernous sinus?
Oculomotor nerve (CN III)
Trochlear nerve (CN IV)
Ophthalmic nerve (V1 branch of trigeminal
Maxillary nerve (V2 branch of the trigeminal)
Carotid (internal) which has sympathetic fibers
Abducens n. (CN VI)
Tributaries (receives from superior and inferior opthalmic veins, sup. parietal sinus, and superior and middle cerebral veins.
Chap 3-WIKI

What is the clinical significance of the cavernous sinus?
It is the only anatomic location in the body in which an artery travels completely through a venous structure.
Chap 3 WIKI

What happens if the internal carotid artery ruptures within the cavernous sinus?
An arteriovenous fistula is created and cavernous sinus syndrome may result from mass effect (also can happen from a tumor) and cause opthalmophegia (from compression of oculomotor, trochlear, and abducens n.; opthalmic and maxillary sensory loss).
Chap 3, FA p.347

Describe where venous sinus' run?
They run in the dura mater where its meningeal and periosteal layers separate.
Chap 3, FA p.347

Describe the drainage patterns of the venous system in the brain.
Cerebral veins --> venous sinus --> internal jugular veins.
Chap 3

What is the middle meningeal artery a branch of and where does it enter through?
Middle meningeal artery (is a branch of the maxillary a) and enters cranium through the foramen spinosum. It supplies most of the dura.

Laceration: epidural hemorrhage
Chap 4

What does the neural tube form?
Neural tube gives rise to the central nervous system (ie brain and spinal cord)
Chap 4

What are the two plates of the brain stem and spinal cord?
Alar plate: gives rise to sensory neurons

Basal plate: gives rise to the motor neurons
Chap 4

The neural tube also gives rise to three primary vesicles which develop into what five secondary vesicles?
1. Forebrain --> Telencephalon and Diencephalon
2. Midbrain --> mesencephalon
3. Hindbrain --> metencephalon and myelencephalon
Chap 4

The five secondary vesicles fetal neural development develop in to what?
1. Telencephalon --> cerebral hemispheres / lateral ventricle
2. Diencephalon --> thalamus / third ventricle
3. Mesencephalon --> midbrain/aqueduct
4. Metencephalon --> pons and cerebellum/upper part of fourth ventricle
5. Myelencephalon --> medulla / lower part of fourth ventricle
Chap 4

What does failure of the anterior and posterior neuropores to close result in (respectively)?
Anterior neuropore: anencephaly (failure of brain to develop)

Posterior neuropore: spina bifida
Chap 4, FA p.342

What are microglia?
Microglia: CNS phagocytes from mesodermal origin. They have small irregular nuclei and very little cytoplasm. In response to tissue damage they transform into large ameboid phagocytic cells.
Chap 4, FA p.342

Can you see microglia on Nissel stains?
Chap 4, FA p.342

What happens to the microglia in patients with HIV infection?
The microglia of patients with an HIV infection fuse to form multinucleated giant cells in the CNS.
Chap 4

When, in gestation, does myelination begin and end?
Myelination begins in the fourth month of gestation and it is not complete until the end of the second postnatal year, when the tracts become functional. Myelination in the cerebral association cortex continues into the third decade.
Chap 4

What myelinates the CNS? Where are these cells not seen?
Oligodendrocytes myelinate the CNS.

They are not seen in the retina.
Chap 4, FA p.342

Oligodendrocytes? Appearance, function, stain?
Oligodendrocytes: each on myelinates multiple CNS axons (up to 30 each). They stain in Nissel stains, appearing as small nuclei with dark chromatin and very little cytoplasm. They are the main glial cell in white matter.
Chap 4, FA p.342

What cells are destroyed in multiple sclerosis?
Oligodendrocytes mainly (myelinate multiple CNS axons)
Chap 4, FA p.342

What myelinates the PNS? How many axons do they each myelinate?
Schwann cells:
Each schwann cell myelinates only 1 PNS axon.
Chap 4, FA p.342

What is an example of a schwannoma and where are they found?
Schwannoma: acoustic neuroma found in the internal acoustic meatus (CN VII, VIII)
Chap 4, FA p.342

What cells line the ventricles?

What cells in brain are involved in phagocytosis?

What neuro cells originate from the ectoderm?
Ependymal cells: line ventricles
Microglia: phagocytosis

Ectoderm: all neuro cells except microglia which, like other macrophages, originate in the mesoderm.
Chap 4, p.342

What is the function of astrocytes? Marker?
Astrocytes: provide physical support,
K metabolism,
help to maintain BBB

Marker: GFAP
Chap 4

Where does the conus medullaris end in the newborn?
Ends at the third lumbar vertebra (L3)
Chap 4

Where does the conus medullaris end in the adult?
Adult: L-1
Chap 4

What is coloboma iridis caused by?
A failure of the choroid fissure to close. This causes a defect in the iris.
Chap 4

What is contained in the choroid fissure?
All the optic nerve fibers
Chap 4

Where did the optic nerve fibers derive from?
Chap 4

Where did the adenohypophysis derive from?
Adenohypophysis is derived from ectodermal mouth cavity called Rathke's pouch.
Chap 4

Rathke's pouch gives rise to the adenohypophysis, what congenital cyst tumor can be formed from Rathke's pouch?
Chap 4

Where did the neurohypophysis develop from?
Neurohypophysis developed from neural ectoderm of the neural tube causing the evagination of the hypothalamus.
Chap 4

Cause of anencephaly (meroanencephaly)?
Anencephaly: results from a failure of the anterior neuropore to close. As a result the brain does not develop.

Frequency: 1:1000
Chap 4

Cause of spina bifida?
Spina bifida results from a failure of the posterior neuropore to form.
Defect usually occurs in the sacrolumbar region.
Chap 4

What is spina bifida occulta? What percent of spina bifida is occulta?
Spina bifida occulta: vertebral arches just don't touch but there are no meninges coming out.

10% of spina bifida is occulta.
Chap 3, p.355

In the cavernous sinus, which is the only nerve that is free floating?
CN VI (abducens)
Chap 3, FA p.355

Where is the cavernous sinus located in respect to the pituitary gland?
The cavernous sinus forms on either side of the pitutary gland.
Chap 3, p.355

What blood does the cavernous sinus house?
Blood from eye and superficial cortex goes through the cavernous sinus into the internal jugular vein.

Also, the internal carotid a. runs through this sinus.
Chap 3, p.355

What bone is anterior to the cavernous sinus?
Sphenoid bone
Chap 3, p.355

Where do the nerves that control extraocular muscles pass through?
The cavernous sinus.
Chap 4

What is cranium bifidum?
Cranium bifidum is a defect in the occipital bone through which meninges, cerebellar tissue, and the fourth ventricle may herniate.
Chap 4

Arnold-Chiari malformation?
Arnold-Chiari malformation:
- elongation of cerebellar tonsils so much that it pushes down through the base of the skull and blocks CNS flow
- in almost all children with spina bifida and hydrocephalus

- has a frequency of 1:1000
Chap 5

Pseudounipolar neurons:
Pseudounipolar neurons:
located in the spinal dorsal root ganglia and sensory ganglia of CN 5, 7, 9, and 10
Chap 4

What is the Dandy-Walker malformation?
Enormous enlargement of the fourth ventricle which is also associated with a small or absent cerebellum (compressed by fluid) and occipital cyst (meningiocele).

Can be in IDed in infancy and can occur in older children.
Chap 4

MCC: stenosis of cerebral aqueduct during development
Excessive CSF accumulates in the ventricles and subarachnoid space.

Cause: can be caused by maternal infection (CMV or toxoplasmosis)
Freq: 1:1000
Chap 4

Fetal alcohol syndrome
Fetal alcohol syndrome:
MCC of mental retardation
Associated with microcephaly and congenital heart defects
Chap 4

Holoprosencephaly: results from a failure of forebrain to develop (telencephalon and diencephalon = lateral and third ventricle, cerebral hemispheres, and thalamus).

The most severe manifestation of fetal alcohol syndrome.
Chap 4

results from bilateral hemispheric infarction secondary to occulsion of the carotid arteries.
The hemispheres are replaced by hugely dilated ventricles.
Chap 5

Where are bipolar neurons found?
Bipolar neurons are found in the cochlear and vestibular ganglia of CN VIII, in the olfactory nerve (CN I) and in the retina.
Chap 5

Where are multipolar neurons found?
Multipolar neurons are the largest population of the nerve cells in the nervous system.
This group includes motor neurons, ANS neurons, interneurons, pyramidal cells of cortex, and Purkinjie cells of cerebellar cortex.
Chap 5

What is Nissel substance?
Nissel: it is a substance found in neurons that consists of rough ER (it makes protein)
It is found in the nerve cell body (perikaryon) and dendrites, not in the axon hillock or axon.
Chap 5

What is Wallerian degeneration?
Wallerian degeneration: when any nerve fiber is cut or chushed there is anterograde degeneration characterized by the dissapearance of axons and myelin sheaths and the secondary proliferation of Schwann cells.

It occurs in the CNS and PNS.
Chap 5

What is chromatolysis?
After nerve damage, this is a loss of the Nissel substance and subsequent retrograde degeneration of neurons in the CNS and PNS.
Chap 5

How does nerve regeneration differ between the CNS and PNS?
CNS: regeneration does not occur. Ex. no regen of optic nerve.

PNS: axon regeneration does occur.
Chap 5 (p.49)

Describe the process of nerve regeneration in the PNS?
2 weeks after injury: there are fewer Nissel bodies in the neuron and macrophages consume the degenerating fiber and myelin sheath

3 weeks: schwann cells proliferate

3 months after injury: if there is organized growth of the schwann cells there is a successful nerve regeneration.
Chap 5

How do astrocytes protect capillaries, neurons, and synapses?
Astrocytes project foot processes that envelop the basement membrane of capillaries, neurons, and synapses.
Chap 5

What neurotransmitters do astrocytes metabolize?
GABA, serotonin, glutamate
Chap 5

What forms glial scars in damaged areas of the brain?
Chap 5

What contains glial fibrillary acidic protein?
Astrocytes: GFAP
Chap 5

What nerve cell contains glutamine synthetase?
Astrocytes (another marker for astrocytes, other than GFAP)
Chap 5

What cells produce CSF?
Ependymal cells (line ventricles)
Chap 5

Where are schwann cells derived from?
Schwann cells: from the neural crest

They are myelin-forming cells of the PNS (1:1)
Chap 5

What are Lewy bodies?
Lewy bodies: neuronal inclusions that are characteristic of Parkinson's dz
Chap 5

What are negri bodies?
Negri bodies are intracellular inclusions caused by rabies. They are found in pyramidal cells of the hippocampus and the Purkinjie cells of cerebellum
Chap 5

What are hirano bodies
Intraneuronal, eosinophilic, rodlike inclusions that are found in the hippocampus of patients with Alzheimer's disease.
Chap 5

What are neurfibrillary tangles
Intracytoplasmic deneraged neurofilaments that are seen in patients with Alzheimers.
Chap 5

What are cowdry type A inclusion bodies?
Intranuclear inclusions that are found in the neurons and glial in herpes simplex encephalitis.
Chap 5

What are nerve fibers Ia and Ib for?
Ia: proprioception and muscle spindles

Ib: proprioception and golgi tendon organs

Both: fastest (70-120m/sec)
Chap 5

What are the nerve fibers II and III for?
II: touch, pressure, vibration

III: touch, pressure, fast pain, and temperature

Speed: 12-70m/sec (II are faster)
Chap 5

What are the nerve fibers IV for?
IV: slow pain and temperature, unmyelinated fibers
Chap 5

What are A-alpha nerve fibers for?
A-alpha: they innervate extrafusal muscle fibers (responsible for generating power of muscle -- mechanical movement). They form the motor unit and are in the ventral horn.

Speed: 15-120m/sec
Chap 5

What are A-gama nerve fibers for?
Gamma nerve fibers - innervate intrafusal muscle fibers that comprise the muscle spindle. These fibers are separated from rest of muscle by a collagen sheath and have sensory receptors.

Intrafusal fibers function to judge position of muscle and rate it is changing.

Speed: 10-45m/sec
Chap 5

Which autonomic nerve fibers are myelinated: preganglionic or postganglionic?
Preganglionic: myelinated

Postganglionic: unmyelinated
Chap 5: FA, p.363

Glioblastoma multiforme
(6 key points)
1. MC primary brain tumor.
2. Life expectancy < 1 yr
3. Found in cerebral hemisphere
4. can cross corpus callosum (butterfly glioma)
5. stain astrocytes with GFAP
6. pseudopalisading tumor cells (border central areas of necrosis and hemorrhage)
Chap 5, FA: p.363

(6 key points)
1. benign, noninvasive tumor of the falx and convex and convexity of the hemisphere
2. 2nd most common primary BT
3. arises from arachnoid cells external to brain
4. resectable
5. has spindle cells concentrically arranded in a whorled pattern (psammoma bodies: laminated calcifications)
6. associated with NF-2
Chap 5: FA: p.363

1. third most common BT
2. Schwann cell origin
3. often localized to 8th nerve (acoustic schwannoma)
4. resectable
5. associated with NF-2
Chap 5, FA: p.363

1. rare
2. slow growing
3. most often in frontal lobes
4. "fried egg" cells - round nuclei with clear cytoplasm
5. often calcified
Chap 5, FA p.363

Pituitary adenoma
(4 key points)
Pituitary adenoma:
1. most common form is prolactin secreting
2. bitemporal hemianopia (due to pressure on optic chiasm)
3. hyper- hypopituitary
4. derived from Rathke's pouch
Chap 5, FA p.363

Pilocytic (low-grade) astrocytoma
(4 key points)
Pilocytic astrocytoma
1. diffusely infiltrating glioma in children
2. most often in the posterior fossa (between foramen magnum and tentorium cerebelli)
3. benign; good prognosis
4. has rosenthal fibers (eosinophilic corkscrew fibers)
Chap 5, FA p.363

(7 key points)
1. highly malignant CEREBELLAR tumor
2. second most common posterior fossa tumor in children
3. can metatastasize through the CSF tracts
4. form of primitive neuroectodermal tumor (PNET)
5. can compress 4th ventricle = hydrocephalus
6. rosettes or perivascular pseudorosette pattern of cells
7. radiosensitive
Chap 5, FA p.363

(6 key points)
1. ependymal cell tumor in children
2. most commonly found in 4th ventricle
3. can cause hydrocephalus
4. poor prognosis
5. characteristic perivascular pseudorosettes
6. rod-shaped blepharoplast (basal ciliary bodies) found near nucleus
7. 60% of spinal cord gliomas
Chap 5, FA p.363

(4 key points)
1. most often cerebellar
2. associated with von Hippel-Lindau syndrome when seen with retinal angiomas
3. can produce erythropoietin leading to secondary polycythemia
4. foamy cells with high vascularity
Chap 5, FA p.363

(6 key points)
1. benign tumor in children
2. confused with pituitary adenoma
3. can also cause bitemporal hemianopia
4. MC childhood supratentorial tumor
5. derived from remnants of Rathke's pouch
6. calfication is common
Chap 5, FA p.343

Meissner's corpusules
Meissner's corpusles:
Small, encapsulated nerve endings found in dermis of palms, soles, and digits of skin.
Light discriminatory touch of glabrous (hairless skin)
Chap 5, FA p.343

Pacinian corpusles
large, encapsulated nerve endings found in deeper layers of skin at ligaments, joint capsules, serous membranes, and mesenteries.
Pressure, coarse touch, vibration, and tension.
Chap 5, FA p.343

Cup shaped nerve endings (tactile disks) in dermis of fingertips, hair follicles, hard pallate.
Involved in light, crude touch.
FA, p.342

What are the peripheral nerve fiber layers?
1. endoneurium: surrounds only a single nerve fiber
2. perineurium (permeability barrier): surrounds a fascicle of nerve fibers
(Perineurium = Permeability barrier, must be rejoined in microsurgery for limb reattachment)

3. Epineurium (dense connective tissue): surrounds entire nerve (multiple fascicles and blood vessels)
Chap 5, FA p.343

What are the two type of free nerve fibers?
Free nerve fibers:
1. nociceptors: pain
2. thermoreceptors: cold and heat
Chap 5, FA p.343

What sensory corpusle is not encapsulated?
Chapter 5: Case 2

4 yo girl presents with clumsiness and headaches.

What tumor is most likely?
Cerebellar astrocytoma (pilocytic astrocytoma: most common in posterior fossa)
Chap 5, p.363, Case 3

63yo female presents with headaches and left-hemiparasis. Tumor cells crossing the corpus callosum can be seen on CT. And can see "psuedopalisading" tumor cells.

What tumor?
Glioblastoma multiforme
Chap 5, p.363, Case 4

53 yo man with severe headaches. CT shows calficiation and hemorrhage in temporal lobe (could also be in frontal lobe).

Oligodendroglioma - mosre likely to show calficifation and hemorrhage than astrocytomas, common in temporal (HY) and common in frontal (FA).
Chap 5, p.363

7yo boy with brain tumor biopsy containing rosenthal fibers:

Pilocytic astrocytoma
(Rosenthal fibers: eosinophilic corkscrew fibers)
Chap 5, p.363, Case 5

2yo girl with nausea and vomiting. Hydrocephaly is seen in lateral ventricle. Periventricular edema is seen along lateral ventricle.

Tumor? Where is it most commonly seen?
Malignant ependymoma:
most common in 4th ventricle
Chap 5, p.363: Case 6

44yo women with headaches. CT shows a tumor with "dural tails".

slow growing and noninvasive

(Case 8 on p.57 shows meningioma at cerebellopontine angle)
Chap 5, p.363: Case 7

38 yo women with ipsilateral hearing loss, tinnitus, and cerebellar ataxia.

Acoustic schwannoma:
p.57: white arrows show expanded interal auditory meatus.
Chap 5, p.363: Case 9

9 yo girl with ataxia, diplopia, and headaches.

What is the DDX? If this tumor is seen in the cerebellum what is the Dx?
DDx: astrocytoma, ependymoma, hemangioblastoma, and chroid plexus papilloma (not craniopharygioma because of no bitemporal hemianopia)

Dx: medulloblastoma
Chap 5, p.363: Case 10

38 yo man with blurred vision and CT with expanded sella turcica:

Tumor? What are side effects?
Pituitary adenoma: side effects most commonly are prolactin secretion: impotence!!!
Chap 5, p.363: Case 11

8 yo girl with headache, weight gain, and anosmia with bitemporal hemianopia.

Craniopharyngioma: these tumors (in children) compress chiasm, pituitary gland (probably stopping TSH release), and third ventricle.

Most common childhood supratentorial tumor.